Epikos

Trying to replace the PCV valve. I'm sure it's never been replaced in the 198k miles on the truck.

My Haynes says to drain coolant and pull a ton of cr@p before you can pull the plenum. I'm wondering if all that is needed?

Can't I just pull the four bolts holding the plenum on, pull it forward a couple inches, replace the valve, and bolt the plenum back on? Maybe replace the knock sensor while I'm in there?

Is there an easy way to pull the plenum without following the whole PITA process in the Haynes guide?

Thanks!
'89 3vz-e pickup.

mudhoney

you could try w/e u want really...uhm take pics first is my advice.
who knows what will give and what will fail if you try just pushing the plenum out of the way.....and you wont be getting to the knock sensor by just moving the p so drop that idea right away. g/l

Zinek

Ok to pull the plenum its a little more than four bolts. To me its a little more work than neccessary. I used very long and big needle plyers and had sprayed it with WD-40 the night before.
I would only deal with knock sensor if it set a code. Besides the upper plenum you will need to remove the intake manifold to get to knock sensor even more work!!!!!

RaginYota

I replaced my PCV without removing the intake. It took a little while, and it was a PITA.

vital22re

iTrader: (2)

its possible to do with some needle nose pliers bent at a 45 they need to be pretty long though.... only pull the plenum upper and lower if you need to change the knock sensor. Even then its more likely the the wiring going from the plug to the sensor is faulty.

scope103

As bad as removing the plenum is, I'll bet I can get it off and back on faster than you can bark your knuckles trying to thread out the PCV valve with needle-nose pliers. (Keep in mind that the nice, soft rubber gasket holding it in place has turned into the consistency of concrete over the years. )

Just one man's opinion.

The reason NOT to remove the plenum is that there is a reasonable chance of breaking something that has been slowly rotting away these last 100,000 miles. The one that got me (and lots others on this list) is the VSV value that controls the fuel vapor cannister.

You drain the coolant a bit to remove the plenum because the throttle body has coolant going through it. You need to remove those lines, and you don't want to pour coolant all over the place when you can just drain a gallon into a bucket.

As already pointed out, the knock sensor is under the intake manifold. Removing the intake manifold requires removing the fuel rails, so you're starting to talk about real work.

If you try the needle-nose pliers route, be very careful with the vacuum lines in that vicinity. You should just mark them carefully, and then move them out of the way.

Good luck!

Zinek

You do not have to remove the fuel rails!!!!... All you do is put a cover on your right fender, unbolt the intake and move it over and place it on your right covered fender with the fuel line and rail on the intake.. Before that unbolt and support the coolant sensor housing so you don't endup breaking it.

Jay351

Removing the upper intake is not a massive task. Search the FSM sticky and use the 93 fsm.


When you get the upper intake unbolted, you can just flip it and lay it on top of the vacuum lines

Epikos

I was looking at it yesterday and I think I might try jacking up the right front to get a better angle at it, and just get my fingers in there; maybe see if the auto store has some 45* needle nose while I'm picking up the valve.

I thought the manual was overstating the complexity of removing the plenum, but I guess not. I did find out its more than the four visible bolts too.

While looking at the PCV valve situation I noticed a lot of oil leakage from the valve cover gaskets. The right front brake line is just about dripping with oil, as well as burnt on oil from many miles ago. I hope a new PCV will help the pressure and lessen the leaks, otherwise I'm now looking at valve cover gaskets in addition to the eventual rear main seal.

dirtbagger

I recently changed my pcv on 93 3vze. i just used long needle nose pliers to pull it out. found a little more difficult to put new pcv in. had to use some dish soap to get er in but it took less time than pulling intake plenum.